Surveyor&#39;s range-finder.



CHARLES P. DONNELL, OF SEQUIM, WASHINGTON.

SURVEYORS RANGE-FINDER.

Specification of Letters Patent.

Patented Apr. 18, 1916.

Application filed July 19, 1915. Serial No. 40,699.

To all whom it may concern.

Be it known that 1, CHARLES P. DONNELL, a citizen of the United States, residing at Sequim, in the county of Glallam' and State of Washington, have invented certain new and useful Improvements in Surveyors Range-Finders, of which the following is a specification.

This invention relates to improvements in range finders employed in surveying operations, and has for its object the provision of simple and conveniently operated devices, including an electrically illuminated lamp, whereby therange of the surveyors target may be known to the transit-man.

The invention is particularly applicable and useful for .employment in relatively dense woods and like occasions where the targets of ordinary construction are difiicult to locate through the poor light and obstructions due to thick foliage and underbrush.

The invention consists in the novel construction of a range finding' staff, and the combination and adaptation therewith of an electrically illuminated lamp as will be fully described in the following specifications, illustrated in the accompanying drawings, and finally set forth in the appended claims.

In said drawings, Figure 1 is a front elevational view of a range staff embodying my invention. Fig. 2 is a fragmentary View in longitudinal section through the said staff and with parts of the mechanism contained therein shown partly broken away. Fig. 3 is a View in longitudinal cross section on line 3..3 of Fig. 2. Fig. 4 is a fragmentary view in front elevation of Fig. 1 drawn to an enlarged scale. Fig. 5' is a view in cross section. on line 55 of Fig. 2.

Referring to said drawings, wherein similar reference characters denote like parts in the several views, the reference numeral 1 indicates a range staff, suchas employed with my invention, having a penetrating point 2 at its lower end. Said staff is desirably formed of rolled sheet metal to afford a casing having a longitudinally arranged chamber 3 therein. Said casing is formed of symmetrical configuration with reentrantly winged portions 4 on its front face separated by 'a vertically arranged slot 5. Adjustably movable in said chamber is a tubular battery shell 6 having a screw threaded plug closure 7 provided with a knurled thumb-piece 8. Bowed springs 10 are provided at the rear of said shell, pressing against the rear of said casingand urging said shell in frictional contact against the inner edges of said wings 4 whereby the shell is maintained in adjusted vertical positions. A metal tab 11 is secured to said shell and projected through the slot 5 whereby said shell may be manipulated to raise, or lower the same as desired.

A dry cell or other battery 12 is adapted to be introduced within said shell through the opening closed by said plug 7 Said battery may be yieldingly supported at its lower end upon coil spring 13 whereby its. central pole piece 15 at its upper end is maintained in contact with a conductor 16 insulated from said shell. Such shell has electrical connections with the opposite pole of said battery, and is in turn electrically connected with one terminal of a miniature electric lamp 17, which is supported in socket 18 mounted upon the upper end of said shell. The opposite terminal of said lamp iselectrically connected with a projecting metallic lug'19 which is arranged to be united in electrical circuit with the conductor 16 by means of a switch member 20. Said switch member is mounted upon a spindle 21 having a finger engaging disk 22 at its opposite end which is formed with spaced notches 23 and 24 which areengageable by spring detent 25 adapted to hold said switch member 20 in its closed and opened positions respectively. Said disk 22 is arranged to project outwardly from the front of the staff to be readily manipulated, while the lamp 17 is arranged to project slightly beyond the slot 5 but its outermost point is arranged to be within a line drawn from the extreme forward ends of the wings 4 whereby the latter afi'ord protection to said lamp from accidental damage.

The operation of the invention may be described as follows: In relatively dark situations, such as in thick woods or underbrush, my invention may be employed as a substitute for the ordinary target rod oras p a means of ascertaining the range in conj unctlon with such rod. The staff is set upright and the current from the battery 12 is caused to flow from one terminal to the other thereof by the closing of the switch member 20, as willbe readily understood,

to illuminate said lamp. The shell may then be raised and lowered within the stafi chamber through the manipulation of the member 11 until the transit man may discover it and thereby ascertain the range.

The invention is extremely simple in its construction, and practical and efficient in operation. It is not subject to damage by the elements, and the entire electrical connections associated with the shell 6 may be removed from the stafi by simply withdrawing the same through the upper end of the stafi.

While I have described my invention with some particularity as to detail, I do not intend to confine myself to the precise construction shown, as, obviously, various modifications and changes may be made within the spirit of the invention and the scope of the claims. I

Having described my invention, what I claim is:

1. In a device of the class described, the combination of a staff having a longitudinally arranged chamber with a slot in its forward side, a shell movable longitudinally Within said chamber provided with a lamp exposed in-said slot, and an electric battery contained within said shell to energize said lamp.

2. In a device of the class described, the combination of a stafi having a longitudinally arranged chamber with a slot in its forward. side, a shell movable longitudinally within said chamber provided with a lamp exposed in said slot, means to retain said shell at adjusted positions within said chamber, and an electric battery contained within said shell to energize said lamp. 1

3. In a device of the class described, the combination of a stafi' having a longitudinnaeoo nally arranged chamber with a slot in its forward side, a shell movable longitudinally within said chamber provided with a lamp exposed in said slot, an electric battery conl tained within said shell to energize said lamp, and a switch to control the illumination of said lamp.

4. In a device of the class described, the combination of a staff formed with a longitudinally arranged chamber and having a slotted opening-into said chamber upon its forward side, said staff being formed of material having reentrantly directed wings upon either side of said opening, a lamp movable longitudinally in said chamber having its forward end projecting through said opening and contained entirely within a line drawn between the outer extremities of said wings.

5. In a device of the class described, the

combination of a staff formed with a longitudinally arranged chamber having a slotted opening in its forward side, a battery shell adjustably mounted in said chamber and adapted to receive an electric battery and transmit the current therefrom, an electric lamp rigidly mounted on said shell in circuit with said battery, and a switch movable with said' shell to open or close said circuit.

Signed at Seattle, Washington, this 30th day of June, 1915.

, CHARLES; P. DONNELL. Witnesses:

HORACE .BARNES,

1E. PnTERsoN. 

